Critical severity · published Jul 30, 2026
CVE-2026-12940
Langflow is affected by remote code execution due to multiple unauthenticated and insufficiently authorized API endpoints
9.8
CVSS
0.9%
EPSS
No
On KEV
Description
IBM Langflow OSS 1.0.0 through 1.10.1 are vulnerable to unauthenticated remote code execution via environment variable injection in the MCP (Model Context Protocol) stdio launcher. The vulnerability exists in src/lfx/src/lfx/base/mcp/util.py where the DANGEROUS_ENV_VARS blocklist fails to include SHELLOPTS , BASHOPTS , and PS4 environment variables.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 61% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LO
Langflow OSS · IBM
1.0.0 through 1.10.1 · source: vendor
LA
Langflow · Langflow
1.0.0 before 1.10.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-12940
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-12940
Vendor Advisory
https://www.ibm.com/support/pages/node/7279995
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